Best electric tankless water heater

The 7 Best Electric Tankless Water Heater Reviews

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Intelligent people save time how far they can, utilize penny the smartest way, and the best electric tankless water heater ensures both of them ideally.

Imagine the morning scenario. You are in a hurry for the office; your wife is preparing breakfast, and the kids are taking a hot shower to get ready for school. After a while, you are entering the bathroom, and the tank water heater is getting refilled and producing hot water for you. There’s no way…You have to wait for the next 30 minutes to get hot water.

So, the tankless water heater is the single solution that offers you a pleasureful hassle-free morning by providing an unlimited amount of hot water flow.

A Quick Overview

If you feel impatient to know the list of our top picked best electric tankless water heater in each particular category, here it is:

My Unbiased Guidelines

I’ve given 100% effort to analyze every single item to provide you an elaborate guideline recommending top electric tankless water heaters for various purposes. 

To make this guide more decent, we have interviewed multiple users and enlisted all functionalities, advantages, inconveniences & written our detailed overview.

I request you to go through my in-depth guide to clarify any confusion about an electric tankless water heater before choosing your suitable model.

Let’s get started… 

TOP 7 ELECTRIC TANKLESS WATER HEATER REVIEWED


1. Best for Whole House Hot Water Supply – Stiebel Eltron Tempra

Stiebel Eltron Tankless Water Heater
  • Warranty: 7 Years Leakage, 3 Years Parts
  • Water Line Requires: 3/4” NPT
  • Activation Flow Rate: 0.50 GPM
  • Input Voltage: 240V
  • Temperature Range: 68F ~ 140F

The Stiebel Eltron assures you an unlimited hot water supply even if you have a large number of family members. You can choose any power variants among the six (12KW, 15KW, 20KW, 24KW, 29KW, 36KW) options according to your whole house demands..

The most impressive technology of the Stiebel Eltron was their invented “auto modulation” of water flow to hold a constant water temperature at your comfort level.

As a result, you never will experience a sudden drop in water temperature while taking a shower or cleaning dishes. 

Even if required, the device will automatically reduce the water flow rate slightly to hold the temperature at an exact point.

The operational procedure is very straightforward. An elegant LED display shows the preset temperature, water flow rate, and any error messages if they occur. By twisting the thermal knob, you can set up your preferred temperature within seconds.

Depending on incoming water temperature and water flow rate, the Stiebel Eltron can maintain heat around 68° F to 140° F.  

Please keep in mind; increasing water flow will decrease the temperature and vice versa, which is a common drawback for every tankless water heater.

Additionally, the larger the watt capacity, the higher the water flow with an extensive hot water temperature. So, in case you need a high amount of water flow, you should choose a high wattage variant of Stiebel Eltron.

Which Should I Choose? Tempra Trend or Tempra Plus 

Most people get confused between Tempra “Trend” and “Plus.” Let’s clarify them.

The Stiebel Eltron Tempra Trend

“Tempra Trend” model has a single programable “Tmax” button and a thermal knob for temperature control. 

You can preset various temperatures between 68F to 140F by twisting the knob or press the Tmax button to get the highest limit.

The Stiebel Eltron Tempra Plus

Tempra Plus” model has 3-buttons and a thermal knob. You can configure the memory button symbolized “1” & “2” for two different temperatures (Suppose, one for Shower & another for cleaning dishes). The “i” button is given to access the menu and the thermal knob for setting up any different temperature.

Along with these operational varieties, the “Plus” variant has some additional features. They are:

  1. Electronically controlled water flow for auto modulation & holding a constant temperature.
  2. The display shows the current water flow rate on GPM and the power absorption.
  3. Calculate the power savings and showcase them on display.

Still, if you are confused about choosing the “Trend” or “Plus,” then I should say, if you need to change water temperature too frequently, then go for Plus.

Otherways, if you don’t require to operate the unit too often and max temperature is okay for you, go for the “Trend” variant.

Which Wattage Variant is the best for me? 

The Stiebel Eltron Tempra is available in six wattage variants (12 KW, 15 KW, 20 KW, 24 KW, 29 KW, 36 KW). The built qualities are the same, but some essential facts might help you choose the right one.

You should consider three key facts for picking the best variant for you.

A. How much hot water demand you have?

B. How cold is your tap water temperature?

C. Is your home electric wiring able to supply the right amount of current?

Firstly, if you have small family members (2-3 person), then 12KW, 15KW, or 20KW units will be suitable, considering how colder the region you live in. If you are from the northern areas, choose the 20KW unit, and the southern area’s people may prefer the 12KW variant. These can easily handle a showerhead (1.5~2.5 GPM) and a kitchen faucet (1.3~2 GPM) at a time. 

Secondly, if you have a medium-size family (3- 4 members) and require more instant hot water flow, considering your living region, 24KW or 29KW variant will be suitable. These models can handle two showerheads (~2.5 GPM) & a kitchen sink (~1.9 GPM) at a time.

Finally, if you have large family members or live in the coldest region, you should choose the highest 36KW variant. You will get a hot water supply in 3 shower heads & 1 sink faucet from this variant at a time.

Please keep in mind

The current consumption of all these variants are:

12KW – 50A ( Require a 50amp single breaker)

15KW – 60A (Require two 30amp breaker)

20KW – 80A (Require two 40amp breaker)

24KW – 100A (Require two 50 amp breaker)

29KW – 120A (Require three 40 amp breaker)

36KW – 150A (Require three 50 amp breaker)

Your home electrical wiring must have the capacity to handle the massive load to run this tankless water heater.

Finally, the 12KW model has a single water heating chamber and one circuit.

The 15KW, 20KW, & 24KW variants have two separate heating chambers and two independent circuits for swift operation, and the 29KW & 36KW unit has three of them. (Shown to the picture).


2. Best Energy Efficient Electric Tankless Water Heater – EcoSmart ECO 27

ecosmart ECO 18 Electric Tankless Water Heater
  • Warranty – Lifetime (Parts & Leakage not the Labour)
  • Voltage – 240V
  • Activation Flow Rate – 0.3 GPM
  • Waterline Connector – 3/4″ NPT
  • Temperature Range – 80F to 140F 
  • Flow Capacity – 2.7GPM ~ 6.5GPM based on inlet water temp.

Suppose you do love energy saver eco-friendly home appliances to cut a decent amount from your electric bills at the end of months. In that case, EcoSmart is something extraordinary that exactly you need.

To enhance energy efficiency Ecosmart ECO 27 tankless water heater distributes load between 3 copper heating compartments equally and resists the higher load on electrical wiring.  

Additionally, Water modulation technology automatically allows the system to consume the exact amount of power to heat the water at your preset level. Thus it saves almost 50% energy comparing to other similar appliances.

With a lifetime warranty, EcoSmart ensures a long-term hot water flow for your whole house. Copper heat exchanger and brass-made heating element protect the inside components from any electrolytic corrosion and keeps them rust-free. 

Not only that, the entire stainless steel body material has enhanced durability at an ultimate level. Thus, EcoSmart offers an extensive warranty too confidently.

With the thermal knob, you are allowed to set the outlet temperature up to 80F~140F, which will be shown on a digital display. Here’s the performance analytics of EcoSmart ECO 27 while the water inlet temperature is 50 degrees Fahrenheit.

Inlet Temperature GPM Outlet Temperature
50F496F
50F3110F
5oF2140F

So, this EcoSmart ECO 27 tankless water heater will be sufficient to deliver hot water at 2X showers (1.5~2 GPM) & 1X (1.3~1.9GPM) kitchen sink and or additional water extensions like laundry and other appliances simultaneously. 

For the lowest activation rate of 0.3GPM, the EcoSmart ECO 27 can perform in city water or even any low-pressure remote water sources.

Please Keep In Mind

  • You will require a 3X 40amp breaker & 8 gauge wire to drive this appliance as it consumes 112+ amp at full throttle.
  • 200 amp electric line capacity is suggested for hassle-free operation.
  • Installation could be DIY with 3/4″ NPT if your electric source is ready.

3. Best Point of Use Electric Tankless Water Heater – Ecotouch 9KW

ECOTOUCH 9KW
  • Warranty – 1 Year Limited
  • Voltage – 240V
  • Temperature Range – 80F ~ 140F
  • Max Flow Capacity – Up to 1.5~2.5 GPM depending on inlet water temp
  • Breaker Required – 1X 40amp Breaker

Ecotouch is most probably the best and smartest-looking tankless water heater I have ever seen. The unit seems no less glamorous than a Black Pearl and will enhance your interior’s elegance with its 2-inch slim rectangular shape. 

For the “point of use” purposes, no other tankless water heater will even appear nearby to its perfection. Regarding features, durability, performance, advanced electronic brains, Ecotouch itself is its own compare.

Where can you use it? Anywhere with a “point of use” purpose includes the kitchen sink, hand sink, laundry outlet, bathroom sink, bathtub, etc.

Suppose you are from southern states, and the inlet water temperature remains above 60F. In that case, Ecotouch will supply a paradise stream of hot water with a single finger touch. Also, you can maintain the temp between 80F to 140F by the ultra-modern touch panel.

Ecotouch has two memory buttons symbolized E1 & E2 for instant access to your favorite preset temperature. With a bright white backlight, the digital display shows the outlet temperature, including heating/standby/overflow status.

ETA approval safety insurance provides us a pleasure of mind. At the insider component, Ecotouch has kept the entire electrical wiring separated from water lines. So the whole unit is safe to use, even for kids.

Please keep in mind, Ecotouch is a point of use appliance. Mainly applicable for sinks, tubs, washing machines, and dishwashers. People from southern states can use it for showers also. 

Ecotouch is extremely easy to mount, and a no-brainer can DIY install it. You will only require a two-pole 40amp breaker and 1/2″ NPT water connection to enjoy this beauty.


4. Best Budget Electric Tankless Water Heater – EcoSmart ECO 11

EcoSmart ECO 11
  • Warranty – Lifetime, Only for parts
  • Voltage – 240V
  • Min Activation flow – 0.3GPM
  • Temperature Range – 80F ~ 140F
  • Max Flow Capacity – 1.7GPM ~ 2.7GPM depending on inlet water temp
  • Breaker Required – 1X 60amp

Suppose you are unwilling to pay a massive amount to replace your old bulky tank water heater with a new electric tankless one. But don’t want to sacrifice the quality, performance & brand reputation, then EcoSmart ECO 11 is blinking at you with a lifetime warranty!!!

Another remarkable fact, with a 0.98 uniform energy factor, EcoSmart performs with 99.8% energy efficiency, results in a 60% reduction of your monthly electric bill. 

This massive reduction of power consumption has been possible for innovative water modulation technology controlled by a central microprocessor and high heat transmissive heat exchanger.

EcoSmart ECO 11 is a 13KW electric tankless water heater designed for single appliances in warmer regions. One bathroom, including shower & sinks, kitchen, essential residential appliances like a washing machine, can easily be supported with this single unit for a smaller family.

Showering with a standard 2 GPM showerhead will never get interrupted with sudden cold water. ECO 11 can supply unlimited hot water at a range of 80F to 140F temperature with a 1.7GPM to 2.7 GPM flow rate depending on inlet temperature. 

You can twist the thermal knob to preset water temperature & the digital display will show it clearly. Pressing the knob for 3 seconds will transform the matrix from Fahrenheit to Celsius and vice versa. 

Enjoying the warm touch of hot water with the ECO 11 is a fact of moments with super easy DIY installation. You will require a 60amp breaker and 1/2″ CF for electrical & plumbing configuration by sequence.


5. Best Electric Tankless Water Heater For Small Family – Rheem RTEX- 18

Rheem RTEX-18
  • Warranty – 5 Year Limited 
  • Voltage – 240V
  • Min Activation flow – Bellow 0.5GPM
  • Temperature Range – 80F ~ 140F
  • Max Flow Capacity – 1.5 GPM ~ 3 GPM depending on inlet water temp
  • Breaker Required – 2X 40amp Breaker

 If you are a part of a small family (husband, wife & kid) and want to upgrade your water heating system into tankless, then Rheem RTEX 18 is an excellent choice to go.

Firstly, Rheem RTEX 18 is a direct competitor of EcoSmart ECO 18. Both are 18KW, contain the same 4.4GPM max hot water flow capacity, and are available in almost the same price range. But, the build quality of Rheem RTEX 18 is better. That’s the reason behind the slightly higher price. 

Revealing a secret!!! EcoSmart ECO is a part of the Rheem family of brands. So Rheem is the mother brand &, of course, provides solid quality comparing EcoSmart. 

Applications that Rheem RTEX 18 can Support

  • Standard Hand Sink ~ 0.5+ GPM
  • Washing Machine for Laundry – 1 ~ 1.5 GPM
  • Kitchen Sink/ Cleaning Dishes – 1 ~ 2 GPM
  • Dishwasher/Similar Appliance – 1 ~ 2 GPM
  • Water-Saver Shower Head (Small) – 1.5+ GPM
  • Standard Shower Head (Large) – 2.0+ GPM
  • Bath Tub – = 4 GPM

Here’s a performance test analytics table of Rheem RTEX 18. 

Inlet Water Temp (F)Water Flow in GPMOutlet Water Temp (F)Temp Raises By (F)
50F1.5 GPM132F82F
50F2 GPM112F62F
50F2.5 GPM99F49F
50F3 GPM91F41F

So, it’s super important to know your inlet water temperature of the region you live in. Although, a slower flow will provide sufficient hot water to you. Rheem RTEX 18 can supply a decent amount of warm water for showers, and the unit can support an entire small family hassle freely.

Installation isn’t that tricky. You will require 3/4″NPT water connections at the bottom line & 2X 40 amps circuit breaker for smooth play.

The unit’s operation is a no-brainer task, simply rotate the thermal knob to preset your comfortable temperature & and the digital temperature will show you the output temperature.

Finally, Rheem RTEX 18 has the same water auto modulation technology as EcoSmart ECO 18 with a 0.98 energy factor. So it works with a 99.8% energy efficiency level saving 60% of electric bills.


6. Best Electric Tankless Water Heater for Laundry Room – Stiebel Eltron DHC – E 8/10

Stiebel Eltron 224201
  • Warranty – 3 years Parts, 7 Years leakage
  • Voltage – 240V
  • Min Activation flow – 0.264 GPM
  • Temperature Range – 86F ~ 140F
  • Max Flow Capacity – 1.7 ~ 2.5 GPM

Stiebel Eltron DHC -8/10 is a fantastic choice for residential laundry tasks. Cause you can configure the unit for both 7.2KW & 9.6KW power consumption according to hot water demand. As a result, the operation for single-purpose “point of use” won’t be that expensive, along with the slim price tag.

The unit can deliver unlimited hot water to a single bathroom sink, kitchen sink, utility sink, or anywhere else you require without delay. Even you may consider this unit using on point of commercial areas like Office Buildings, Gas Stations, Stores, Schools, Malls, Hotels / Motels, Warehouses, Commercial Condominiums, or in restaurants.

The main drawback of the unit, it can’t supply hot water in multiple sources simultaneously. Or in the coldest area, this might not be sufficient for providing enough hot water at showerheads. 

Otherways, for laundry & sink purposes, it’s a great choice. Or you may also prefer the unit for the bathtub if you don’t mind refilling the tub a bit slowly. 

Using the thermal regulator, you can configure the unit at 86F to 140F, and depending on inlet water temperature, it can flow up to 1.3~3 GPM hot water at a time. You will require a 50amp breaker to operate this unit smoothly.

Finally, this unit has a microprocessor to monitor advanced level water temperature, which is too exact, flow activation, energy-saving & ensuring all user’s safety. As a result, it can outperform any traditional bulky tank water heater with a tiny, elegant shape.


7. Best Electric Tankless Water Heater For Commercial Use – Eemax EEM24027

Eemax EEM24027
  • Warranty – 5 Year Leakage, 1 year Parts
  • Voltage – 240V
  • Min Activation flow – Bellow 0.5GPM
  • Temperature Range – 80F ~ 140F
  • Max Flow Capacity – Up to 5.3 GPM depending on inlet water temp
  • Breaker Required – 3X 40amp Breaker

Commercial sectors need a high volume of hot water to fulfill their demand, and the commercial appliance should be more durable to adapt to those heavy uses. The Eemax EEM24027 meets both of these criteria.

Eemax performs significantly well in warmer regions and able to supply hot water to 4-5 utility sinks at a time. Also, it’s capable of handling the hot water demand of an entire commercial kitchen, laundry, or shower. For the restaurant owner, hotels, malls, warehouses, Eemax will serve you like a charm. 

This unit can simultaneously supply hot water to 4 standard showerheads in warmer weather without dropping water temperature with a rating of 5.3 GPM water at max, depending on the inlet temperature. You can control it between 80F to 140F by twisting the thermal knob. 

The digital display shows outlet temperature in both the Celsius and Fahrenheit unit according to your preference. 

Eemax EEM24027 is a 27KW appliance that consumes around 112.5 amp currents and requires 240V to run. You will need 3X 40amp breaker for uninterrupted operation and can do a DIY installation with basic plumbing knowledge.

Eemax has designed for heavy-duty operation. The internal components are entirely safe to use, and electronic functionality ensures minor power consumption. So, it’s the ultimate commercial package.


Be Aware of these facts before you go for Tankless. 

No appliance is entirely perfect. The electric tankless water heater isn’t an exception. They have a few limitations, drawbacks which could remain you unsatisfied. So, before facing those situations, ensure you can adapt to them.

Drawback 1: Limitation of raising water temperature too high

A tankless water heater never raises water temperature as high as a tank water heater can do. Even if you set up the highest temp, the tankless system can hardly reach that top point. Additionally, increasing water flow will decrease water temperature and vice versa. 

While a tank water heater can reach a temperature near the boiling point, the tankless one can hardly reach up to 140F. With a decent amount of water flow, you should expect water output not more than 110F. 

Generally, water flow from the tankless water heater is sufficient for showering, dishwashing, kitchen stuff, and daily life needs. But if you require a massive temperature, you should think twice or straightly should go for the tank.

Drawback 2: Require High Load Electrical Wiring

The tankless water heater consumes 10X more current comparing a tank water heater. While the highest load of a tank water heater could be 3KW, a tankless water heater requires around 9KW to 36KW power load depending on size, which is massive.

Several electric outlets can’t handle this electric load to run the appliance soundly. Although nowadays most of the houses have this capacity to take a high load for this appliance.

Suppose you are from any remote locations or own historic houses with poor electrical wirings. In that case, you will require new wiring with 8 AWG gauge cable 240V connection with a relevant circuit breaker in case you want a tankless system installation.

Drawback 3: Require More Maintainance 

I know people use an old convention tank water heater for longer than 20 years & entirely maintenance-free. You should not expect it from an electric tankless water heater as it may take some minor maintenance over time. In most cases, they could be a DIY project, but some rare critical issues may require professionals. 

Then Why Should I Prefer the Electric Tankless Water Heater?

Despite having some drawbacks, electric tankless water heaters are the best choice to pick. No other system can provide an unlimited hot water flow during a long shower, but the tankless water heater. 

A water heater with a tank has a limitation of hot water holding capacity, and while having a shower or other types of uses, the tank starts getting refilled with cold water. As a result, you experience a gradual temperature drop over time. For the same reason, the tank water heater provides hot water 3/4 of its capacity. 

Again, the tank water heater takes around half an hour to reheat the water and make it ready to use. 

Another hidden fact of old tank water heaters, the water that remains unused inside the hot water tank consumes electricity to remain hot. As a result, you pay more bills for unused hot water, which is a clear waste of money.

The electric tankless water heater keeps you free from all of these hassles and lets you enjoy an unlimited shower whenever you want without a single delay.

Accordingly, as there is no way to preserve hot water and maintain the temperature, there is no energy wastage. Thus electric tankless water heater saves almost 60% water heating cost every month.

Why should I choose an “ELECTRIC” Tankless water heater Instead of gas?

If you have a higher load capacity electrical wiring, then an electric tankless water heater is recommended instead of gas. Cause

  • Gas energy is expensive than electricity
  • Gas tankless water heater requires ventilation, which an electric tankless water heater doesn’t.
  • The gas tankless water heater has an ignition issue, while the electric tankless water heater is 100% automatic.
  • The electric tankless water heater is entirely soundless, while the gas water heater roars like a jet engine.
  • Gas water heater emits toxic NOx; on the other hand, there is no similar issue with the electric tankless water heater. 
  • Electric tankless water is entirely safe to operate and remains cold to touch, but gas tankless water heater remains too hot like an exhaust pipe.

So, there is no way of choosing a gas tankless water heater for indoor use unless you don’t have access to electricity. The electric tankless water heater is the safest and most intelligent solution for home & commercial indoor services.

How the Environment Water Temperature Impact Tankless Water Heater Performance?

This is arguably the most important factor before choosing a tankless water heater. I seek your concentration on this section for a better understanding.

The display on an electric tankless water heater shows the preset outlet water temperature that you desire to get. But do you receive the exact temperature? 99% time, never. You receive a lower temperature than the temperature display shows. Here is the reason.

Setting the temperature 140F doesn’t mean the tankless water heating unit will deliver 140F hot water. It does mean the system will utilizing high power capable of producing 140F hot water. And here is the game. 

If your environment water temperature remains 59F, the system has to raise it by 81F to reach towards 140F temp point.  

So, if the highest power consumption of your tankless water heater can raise the water temperature by 81F, then you can only receive 140F hot water if your environment water temperature remains at 59F. What if the environment temperature remains at 49F? You will receive a 130F hot water output, although you have preset the output temperature at 140F.

Additionally, increasing water flow will decrease water temperature and nothing to do with this. 

Considering all these scenarios, knowing your environment water temperature is a must before buying your preferred model.

Here is a temperature map to decide better while choosing the right size of the tankless water heater. 

Let’s do some small calculations to prefer your perfect model. Suppose the water inlet temperature of your region is around 60F, and the water heater you require should look like

Inlet Water Temp (F)Water Flow in GPMOutlet Water Temp (F)Temp Raises By (F)
60F1.5 GPM142F82F
60F2 GPM122F62F
60F2.5 GPM109F49F
60F3 GPM101F41F

3GPM at 101F is the perfect amount of hot water for running two standard showerheads simultaneously. So if the water heater is capable of supplying this amount, that might be sufficient for your requirement. For higher, higher, or lower demand, you need to increase or decrease the Kilo Watts.

Thus you can choose the perfect electric tankless water heater for suits all your demands.

What size of Electric tankless Water heater do I need?

Please read my first product review, where I have already provided the sizing info depending on several scenarios. 

This fact depends on three different elements.

  • How much GPM do you require at a time?
  • What is the average environmental water temperature of your region?
  • How many amp your electrical outlet can supply?

Considering that your home electrical wiring system can provide a high amp of current flow around 200A (recommended), here are some scenarios to match your requirements. 

A small family or small demands should choose around 13KW -18KW depending on inlet water temperature.

Medium family or medium demand like 4 GMP can be covered by 20KW to 27KW tankless unit. Of course, it depends on the inlet water temperature.

27KW to 36KW units may cover large family, commercial uses, or significant water demands. 

For “point-of-use” purposes, I would recommend a 9KW unit or a smaller one.

But, the fact I should remind you repeatedly, please don’t forget considering inlet water temperature, otherways your entire investment for the electric tankless system will be worthless.

How Cost-Efficient are the Electric Tankless Water Heaters?

The most significant advantage of these appliances is cost-efficiency. To clarify this, I should compare it with a 30 Gallon tank water heater which is around 5-kilo watt.

Suppose you need 90 gallons of hot water a day, and it takes 2.5 hours to produce this amount of hot water. For maintaining the temperature, the system requires running an additional 2.5 hours throughout the rest of the day. 

So totally, the system remains active for 5 hours and consumes 5×5 = 25KWhr or 25 units of electricity.

On the other hand, if you use an electric tankless system of 10 KW. All the family members take showers for 1 hour and an additional 1 hour to complete all dishwashing tasks and laundry. So the system will remain active not more than 2 hours a day, consuming 2×10 = 20KWhr or 20 units of electricity, which is 25% lower than the tanked one. 

In the real-life, a tankless water heater’s operational costs are almost 50% less than the tanked one cause; the system never consumes the total power. The reason, during the shower, you never need steaming hot water. The kitchen sink requires hot water, but that’s a minimal amount of time.

Installation and Maintenance, Can I do it Myself?

In most cases, yes. Suppose you have some basic plumbing and electrician knowledge, then 100% yes.

You would just require an electrical connection with 8-gauge wire, connecting the breakers, and the water inlet/outlet connections with flexible pipes.

The most critical task here is connecting the breakers. If you are confident that the entire installation will take not more than a couple of hours.

To ensure the correct connection diagram, read the manual carefully. Otherways the unit will get damaged.

Connecting the waterline, check the system is leakage-free.

Then you are ready to go.

Note: Highering, a plumber, and an electrician is a far better deal than destroying the unit or occurring an accident by an unprofessional hand!!! 

Maintainance: In 99% of cases, the maintenance is changing the breakers and cleaning the units, which you can do easily. If any critical error happens, then claim a warranty or hire professionals.